Python While Loops

A while loop allows you to execute a block of code as long as a specified condition is True. This is useful for scenarios where you need to repeat an action until a certain condition changes.

Basic While Loop

The basic syntax of a while loop is as follows:

The while loop will continue to execute the indented code block as long as the condition remains True.

while condition:
    # Code to be executed

In this example, the loop will print the value of count and increment it by 1 each time, until count reaches 5.

count = 0
while count < 5:
    print("Count:", count)
    count += 1

While Loop with Else

You can also include an else block with a while loop. The else block will be executed when the condition becomes False.

The else block runs after the while loop completes normally.

count = 0
while count < 5:
    print("Count:", count)
    count += 1
else:
    print("Count reached 5")

Infinite While Loop

An infinite loop occurs when the condition of a while loop never becomes False. This should generally be avoided unless intentionally used (e.g., in servers). An infinite loop will continue to run indefinitely unless externally stopped.

while True:
    print("This is an infinite loop. Press Ctrl+C to stop.")

Breaking out of a While Loop

You can use the break statement to exit a while loop prematurely, even if the condition is still True. The break statement immediately terminates the loop.

count = 0
while count < 10:
    print("Count:", count)
    if count == 5:
        break
    count += 1

Skipping Iterations in a While Loop

The continue statement skips the current iteration and moves to the next iteration of the loop. It allows you to skip specific iterations based on a condition.

count = 0
while count < 10:
    count += 1
    if count % 2 == 0:
        continue
    print("Odd Count:", count)

Python While Loops Example Code

This program uses while loops to print numbers, break out of the loop prematurely, and skip certain iterations.

# Basic while loop
count = 0
while count < 5:
    print("Count:", count)
    count += 1

# While loop with else
count = 0
while count < 5:
    print("Count:", count)
    count += 1
else:
    print("Count reached 5")

# Infinite while loop
# Uncomment the lines below to run an infinite loop
# while True:
#     print("This is an infinite loop. Press Ctrl+C to stop.")

# Breaking out of a while loop
count = 0
while count < 10:
    print("Count:", count)
    if count == 5:
        break
    count += 1

# Skipping iterations in a while loop
count = 0
while count < 10:
    count += 1
    if count % 2 == 0:
        continue
    print("Odd Count:", count)

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